Field of the Invention
The invention relates to a manufacturing method of a circuit board and a stamp, and more particularly, to a piezochromic stamp and a manufacturing method of a circuit board formed by the piezochromic stamp.
Description of Related Art
Nano-imprint lithography (NIL) is a technique for manufacturing fine circuits and is extensively applied in the LED and OLED industries. NIL includes pressing a mold prototype having a pattern (generally referred to as mold, stamp, or template) on an etchant or a photoresist to mechanically deform the mold prototype so as to precisely transfer a fine pattern. Therefore, once the manufacture of the mold is complete, a fine structure such as a nano structure can be repeatedly molded in a simple manner, and manufacturing costs and the production of harmful waste in the manufacture can be effectively reduced. As a result, NIL has been expected to be applied in various areas in recent years.
However, after NIL transfers a pattern to a photoresist using a mold, comprehensive exposure needs to be performed, and therefore the patterned photoresist layer to be formed and the unnecessary residual photoresist layer are both exposed to light. As a result, the residual photoresist layer cannot be removed by a developing solution in a simple manner. Therefore, unnecessary residual photoresist layer needs to be removed using inductively-coupled plasma (ICP) or reactive ion etching (RIE), such that the photoresist pattern to be formed is readily damaged and the process yield is poor. Therefore, how to remove the residual photoresist layer without damaging the fine pattern transferred to the photoresist layer is an important topic for the industry.